Expanding auger



Oct. 17, 1939.

's. G. RUDDELL'EI' AL EXPANDING AUGER Filed Feb. 26, 1938 ni i All/[mow 6.6. Ruoocu T. Fmam W Patented Oct. 17, 1939 PATENT OFFICE EXPANDING AUGER Stuart G. Ruddell and Thomas Fraser, Winnipeg, Manitoba, Canada Application February 26, 1938, Serial No. 192,866 In Canada March 8, 1937 1 Claim.

This invention relates to a process and apparatus for carrying out this process, the process itself consisting in the formation of a mold of substantially frusto-conical configuration, the

said mold being designed to receive concrete which when hardened, will form a footing for the support of a superimposed structure or a pile, the base of the footing being relatively wide with'respect to the apex to resist downward thrust of the structure thereabove with the use of the minimum amount of concrete.

A further object of this invention is to provide a device by the use of which a subterranean mold of substantially frusto-conical configuration may be formed.

A further object of the invention is to provide a device of the character herein described which is equipped with a plurality of spoon-like members designed to form a cup when the device is closed in which loosened earth may be withdrawn from the drilling.

A further object of the invention is to provide a device of the character herein described which is designed to be first introduced into a straight drilling and then expanded in order to flare the drilling.

A further object of the invention is to provide a device of the character herein described which is of rugged construction and is adapted for easy replacement of worn or damaged parts.

A still further object of the invention is to provide a device of the character herein described which is simple to construct, economical to manufacture and cannot easily become out of order.

With the above more important objects in view and such other minor objects as may appear as the specification proceeds, our invention con sists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawing, in which:

Fig. 1 illustrates an elevational view of our auger with the blades thereof in a partially expanded position.

Fig. 2 illustrates a vertical sectional view of the form of drilling made with this auger.

Fig. 3 is a sectional view taken on the line 33 Figure 1.

Fig. 4 shows a fragmentary plan view of a few of the blade teeth.

In the drawing like characters of reference indicate corresponding parts in the different figures.

This invention consists of a central square shaft I, the tip 2 of which is made circular in formation and is tapered in the manner illustrated. A circular base plate 3 is secured to the shaft by a set screw 4 or other means and is provided with four metallic strips 5 on the upper surface thereof which are located on the quadrant lines. The outer end of each of these strips is thickened and drilled to form a bearing 6 in which is journalled a pin 1.

Slidably mounted upon the shaft I is an elongated square sleeve 8. A cross bar 8 is attached to the upper end of the sleeve for manual operation of the device and a disc 9 is secured adjacent the lower end thereof. The under surface of this disc is provided with four pairs of spaced brackets II] which are designed to receive pins I I.

Extending between the plate 3 and the disc 9 are four articulated blades I2 consisting of elongated upper portions I3 to which are pivotally attached shorter connecting arms I4. The cutting edges of the blades are provided with a plurality of coarse bevelled teeth I5 formed therein.

Attached to one side of each of the arms I4 is a scoop I6. When the sleeve 8 is raised and the blades assume a vertical position, the four spoons I6, together with the arms l4 form a cup in which earth may be withdrawn from a drilling.

The structure of this device having been set forth, the mode of operation thereof will now be presented.

A straight drilling I1 is first made in the ground with an ordinary auger to the desired depth. The sleeve 8 is then raised by means of the cross bar 8', until the blades I2 lie adjacent the central shaft at which time, the device may be lowered into the drilling already formed. The tip 2 of the shaft will penetrate below the base of the drilling and form a pivotal point about which the device may revolve. The auger is now rotated through the medium of the sleeve 8 and coincidentally therewith, the same is forced slowly downwardly. This downward movement will cause the blades to distend and as the device is revolving, will obviously flare the lower end of the drilling in the manner illustrated in Figure 2, the blades finally assuming the position indicated by the phantom lines in Figure 1.

It should be pointed out that at intervals during the flaring operation, the sleeve 8 is raised at which time, the earth is caught between the four spoons I6 and the whole structure is then lifted from the ground and the earth removed therefrom prior to re-insertion.

From the foregoing, it will be apparent that we have designed a simple and rugged piece of 55 mechanism with which to form in the minimum of time and with the minimum amount of labor, a mold of substantially frusto-conical configuration at the lower end of a subterranean drilling or immediately below ground level which when filled with concrete, will provide an effective footing possessing a relatively large bearing surface in relation to the amount of concrete used.

Since various modifications can be made in the above invention, and many apparently widely difierent embodiments of same, made within the scope of the claim without departing from the spirit and scope thereof, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense and we desire only such limitations placed thereon as are specifically expressed in the accompanying claim.

What we claim as our invention is:

An implement for forming a subterranean mold of substantially frusto-conical configuration to receive the cast-in-place footing for a cast-in-place concrete pile resting vertically upon the apex thereof, comprising a horizontally disposed circular bearin-g plate, a concentrically positioned point extending downwardly from the under side of said plate and designed to extend into the ground therebeneath to provide a stationary axis of rotation for said implement, a plurality of excavating blades hingedly secured to the perimeter of said plate, a scoop upon the rear edge of each of said blades, means for rotating said implement in the form of a hollow sleeve of polygonal interior cross-sectional configuration, a circular top plate concentrically positioned at the lower end of said sleeve, a shaft of polygonal cross-section secured at its lower end concentrically to said base plate, the upper end of said shaft extending into said sleeve and being slidable therewithin, a plurality of further blades hingedly secured at'the upper ends thereof to the perimeter of said'top plate and at the lower ends thereof hingedly to the outer ends of said first mentioned blades, a downward force exerted upon said sleeve causing said last mentioned blades to diverge at the lower ends thereof and said first mentioned blades to move towards the horizontal, an upward force upon said sleeve causing said last mentioned blades to converge at the lower ends and said first mentioned blades to move towards the vertical about the points at which they are hinged to said base plate, and also causing said scoops together with said first mentioned blades to form a receptacle for dirt removed during the rotation of said implement against the wall of the mold in which the same is being worked.

STUART G. RUDDELL. THOMAS FRASER. 

